LayerFunctions<F1, F2, ...>
Returns (32768 - (32768 - F1) * (32768 * F2) / 32768) This is the same as 1-(1-F1)*(1-F2), but multiplied by 32768. Basically Mix<LayerFunctions<F1, F2>, A, B> is the same as Mix<F2, Mix<F1, A, B>, B>.
Mix
https://github.com/profezzorn/ProffieOS/blob/6f8add544c627172ad2dd698c90e5e55078a420a/functions/layer_functions.h#L4